"They really did everything they could possibly do at that time. Clearly if they had had radar, that could have prevented that," said Stephanie L. Keimig, Boy Scouts resident camp director at Treasure Valley. "Now we have computer access and we can see live radar. That allows us to see where the storm is and its intensity."

The state requires recreational camps for children to submit disaster plans for emergencies, including severe weather to local boards of health before they can be licensed to operate. Most have horn or alarm systems to signal the type of emergency and what staff and campers are to do. Camps train their staff prior to campers' arrival and hold drills each week during camp. Parents are also informed of disaster plans.

KT Therrien, logistics manager at Nature's Classroom in Charlton, said the camp's disaster plan worked perfectly to keep the more than 200 children safe when a tornado hit on June 1, 2011.

She said as the tornado watch was announced, staff began making sure everybody was accounted for and where they were supposed to go. When the tornado warning came, the children were brought inside buildings and then moved to the basement area as the storm approached.

"I was watching the radar and saw the timeline. We got them in about 20 minutes before it hit," she recalled. "None of our buildings were hit, but it went through the wooded area of the property and we lost a lot of trees."

The area probably isn't seeing more tornados than 30 years ago, but more are being reported because of Doppler radar and trained civilian weather spotters, said Glenn Field, warning coordination meteorologist with the National Weather Service in Taunton. He said the number of weather spotters trained by the NWS to observe the weather and report severe weather has increased from about 400 in 1993 to 6,800 now.

He said people should take a tornado warning as well as a tornado watch seriously. A watch, he said, means you can go about your normal business, but pay close attention to the sky and weather reports. A warning means a tornado has been sighted or reported or is imminent, he said. People should immediately seek safe shelter during a tornado warning.

"A warning is the most serious. It's like if your mother yells at you and says, 'I'm warning you,' that's pretty serious," Mr. Field said.

Amanda K. Anderson, program director for Girl Scout camps in Central and Western Massachusetts, said during a recent tornado warning, children at Camp Eyrie in Harvard were directed to go to basements in two of the buildings.

But, like many old camps, Hickory Hill, a Girl Scouts camp in Whitinsville, does not have buildings with basements. In case of a severe thunderstorm or tornado warning or watch, children are directed to inner rooms of buildings. But the camp can also depend on the local Fire Department. In the past, the Fire and Police departments have transported Hickory Hill campers to the fire station to ride out severe storms.

"When we get any severe weather report when they're in session, we make the call over there right away to let them know. And we will evacuate if we have to, which we've done in the past," Northbridge Fire Capt. David M. White said.

Sandy Scola, early childhood director at the Worcester Jewish Community Center, said directors of the three camp programs at the JCC contact one another by walkie-talkie and get together to assess what safety measures need to be taken, or if the weather just needs to be monitored. The JCC has a basement where the campers and staff can seek shelter in case of a tornado. In an emergency, the JCC reaches parents by email, though it is working on putting a text message emergency system in place, she said.

July 1, an EF1 tornado hit Connecticut, from Windsor Locks to East Windsor, according to the National Weather Service. Sports World, a football club in East Windsor, lost the dome over its soccer field to the tornado, while campers were on the premises. Kathleen Russotto, director for the summer camp, said she got the 29 campers, ages 5 to 12, and five counselors out of the soccer dome 15 to 20 seconds before the dome was ripped off.

Ms. Russotto said she first became aware of the tornado warning through the weather alert on her cellphone. She went into the soccer dome, which is adjacent to the hard structure on the premises, and blew her whistle to get everyone's attention and ushered them into the hard structure.

When they were there, she had everyone get under tables to protect themselves. When she looked outside again, the dome was gone.

"The dome is made to withstand wind, but this was very high wind," Ms. Russotto said. No one at Sports World suffered any injury. Ms. Russotto and the other counselors used their cellphones once the tornado had passed to reach the parents of the campers.

A bigger threat than tornados is lightning, said Mr. Field with the National Weather Service.

"Lightning kills a lot more people than tornados in this area," he said, noting that 25 campers were injured by lightning in New Hampshire a couple of weeks ago.

He suggested people invest in a portable hand-held lightning detector, which costs about $70.

He also said there is a simple saying that can teach people about thunder and lightning: "When thunder roars, go indoors. If you can hear it, fear it. If you can see it, flee it," he said.

"Any thunderstorm can cause a lightning fatality," he added. "Basically, if you can hear thunder, you're close enough to be struck. The only safe place is indoors."

Contact Elaine Thompson at ethompson@telegram.com. Follow her on Twitter @EThompsonTG